Implements the Property method on the Stylesheet class, so it can be used from the backoffice.

Completes U4-934

src/Umbraco.Core/Models/Stylesheet.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Runtime.Serialization;
+using System.Text;
 using Umbraco.Core.IO;
 using Umbraco.Core.Models.Css;
 using Umbraco.Core.Models.EntityBase;
@@ -21,8 +22,14 @@ namespace Umbraco.Core.Models
         }
 
         /// <summary>
-        /// Returns a list of <see cref="StylesheetProperty"/>
+        /// Returns a flat list of <see cref="StylesheetProperty"/> objects
         /// </summary>
+        /// <remarks>
+        /// Please note that the list is flattend by formatting single css selectors with
+        /// its value(s). Blocks in css @ rules are also flatten, but noted as part of an @ rule
+        /// by setting the <see cref="StylesheetProperty"/> property IsPartOfAtRule=true.
+        /// This is done to make the stylesheet usable in the backoffice.
+        /// </remarks>
         [IgnoreDataMember]
         public IEnumerable<StylesheetProperty> Properties
         {
@@ -31,23 +38,78 @@ namespace Umbraco.Core.Models
                 var properties = new List<StylesheetProperty>();
                 var parser = new CssParser(Content);
 
-                //TODO Need to explorer how the Stylesheet should be iterated to generate a list of css properties
                 foreach (CssAtRule statement in parser.StyleSheet.Statements.Where(s => s is CssAtRule))
                 {
-                    properties.Add(new StylesheetProperty(statement.Value, ""));
+                    var cssBlock = statement.Block;
+                    if(cssBlock == null) continue;
+
+                    var cssValues = cssBlock.Values;
+                    if(cssValues == null) continue;
+
+                    properties.AddRange(FormatCss(cssBlock.Values, true));
                 }
 
-                foreach (CssRuleSet statement in parser.StyleSheet.Statements.Where(s => s is CssRuleSet))
-                {
-                    var selector = statement.Selectors.First();
-                    var declaration = statement.Declarations.FirstOrDefault();
-                    properties.Add(new StylesheetProperty(selector.Value, declaration.ToString()));
-                }
+                var statements = parser.StyleSheet.Statements.Where(s => s is CssRuleSet);
+                properties.AddRange(FormatCss(statements, false));
 
                 return properties;
             }
         }
 
+        /// <summary>
+        /// Formats a list of statements to a simple <see cref="StylesheetProperty"/> object
+        /// </summary>
+        /// <param name="statements">Enumerable list of <see cref="ICssValue"/> statements</param>
+        /// <param name="isPartOfAtRule">Boolean indicating whether the current list of statements is part of an @ rule</param>
+        /// <returns>An Enumerable list of <see cref="StylesheetProperty"/> objects</returns>
+        private IEnumerable<StylesheetProperty> FormatCss(IEnumerable<ICssValue> statements, bool isPartOfAtRule)
+        {
+            var properties = new List<StylesheetProperty>();
+
+            foreach (CssRuleSet statement in statements)
+            {
+                foreach (var selector in statement.Selectors)
+                {
+                    var declarations = new StringBuilder();
+                    foreach (var declaration in statement.Declarations)
+                    {
+                        declarations.AppendFormat("{0}:{1};", declaration.Property, FormatCss(declaration.Value));
+                        declarations.AppendLine("");
+                    }
+                    properties.Add(new StylesheetProperty(selector.Value.TrimStart('.', '#'), declarations.ToString()) { IsPartOfAtRule = isPartOfAtRule });
+                }
+            }
+
+            return properties;
+        }
+
+        /// <summary>
+        /// Formats a <see cref="CssValueList"/> to a single string
+        /// </summary>
+        /// <param name="valueList"><see cref="CssValueList"/> to format</param>
+        /// <returns>Value list formatted as a string</returns>
+        private string FormatCss(CssValueList valueList)
+        {
+            bool space = false;
+            var values = new StringBuilder();
+
+            foreach (CssString value in valueList.Values)
+            {
+                if (space)
+                {
+                    values.Append(" ");
+                }
+                else
+                {
+                    space = true;
+                }
+
+                values.Append(value);
+            }
+
+            return values.ToString();
+        }
+        
         /// <summary>
         /// Boolean indicating whether the file could be validated
         /// </summary>
@@ -71,11 +133,30 @@ namespace Umbraco.Core.Models
         /// <returns>True if css is valid, otherwise false</returns>
         public bool IsFileValidCss()
         {
-            var parser = new CssParser(Path);//TODO change CssParser so we can use Content instead of Path
-            return parser.Errors.Any();
+            var parser = new CssParser(Content);
+
+            try
+            {
+                var styleSheet = parser.StyleSheet;//Get stylesheet to invoke parsing
+            }
+            catch (Exception ex)
+            {
+                //Log exception?
+                return false;
+            }
+            
+            return !parser.Errors.Any();
         }
     }
 
+    /// <summary>
+    /// Represents a Stylesheet Property
+    /// </summary>
+    /// <remarks>
+    /// Properties are always formatted to have a single selector, so it can be used in the backoffice
+    /// </remarks>
+    [Serializable]
+    [DataContract(IsReference = true)]
     public class StylesheetProperty : IValueObject
     {
         public StylesheetProperty(string @alias, string value)
@@ -86,5 +167,6 @@ namespace Umbraco.Core.Models
 
         public string Alias { get; set; }
         public string Value { get; set; }
+        public bool IsPartOfAtRule { get; set; }
     }
 }